20661103 has 4 divisors (see below), whose sum is σ = 21876480. Its totient is φ = 19445728.

The previous prime is 20661101. The next prime is 20661119. The reversal of 20661103 is 30116602.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20661103 - 2¹ = 20661101 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20661101) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 607663 + ... + 607696.

It is an arithmetic number, because the mean of its divisors is an integer number (5469120).

Almost surely, 2^20661103 is an apocalyptic number.

20661103 is a deficient number, since it is larger than the sum of its proper divisors (1215377).

20661103 is a wasteful number, since it uses less digits than its factorization.

20661103 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1215376.

The product of its (nonzero) digits is 216, while the sum is 19.

The square root of 20661103 is about 4545.4486027234. The cubic root of 20661103 is about 274.4002488686.

Adding to 20661103 its reverse (30116602), we get a palindrome (50777705).

The spelling of 20661103 in words is "twenty million, six hundred sixty-one thousand, one hundred three".